[Testing] Implement wait-for-condition mocking

Migration from https://github.com/aws/aws-durable-execution-sdk-python-testing/issues/46

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## Context
Add condition registration and monitoring for wait-for-condition operations

## Technical Requirements
- Add condition registration and monitoring for wait-for-condition operations
- Implement condition mocking mechanism to trigger completion
- Add condition evaluation and timeout handling
- Implement proper error handling for condition failures

## Acceptance Criteria
- [ ] Condition registration and monitoring added for wait-for-condition operations
- [ ] Condition mocking mechanism implemented to trigger completion
- [ ] Condition evaluation and timeout handling added
- [ ] Proper error handling implemented for condition failures

Start by reviewing migrated issue 46 and locating the existing wait-for-condition entry point in the Python SDK. Define completion against the listed acceptance criteria: registration and monitoring, mocked completion, condition evaluation with timeouts, and error handling for failures.

Written by the indexing model from the issue text.